Learning French: when and why do we say un de ces quatre?

You may have noticed that quite a few French expressions feature the number four - here is one to add to the list.

Un de ces quatre is used in casual informal conversation, often when unsure of the exact time you will next see someone. 

This mysterious phrase sparks questions surrounding its meaning, origins and even spelling. 

What does un de ces quatre mean?

This slightly obscure French expression literally translates as: one of these four. In English, more fitting translations include:

• One of these days - un de ces jours

• Soon - bientôt/prochainement

• At some point or another - à un moment ou à un autre

This expression refers to an event that might happen in the near future but the exact time is unclear. 

It is often used when leaving someone and being unsure of when you will see them again. 

Read also: Exploring 'bonne continuation': meaning and usage in French culture

What are the origins of un de ces quatre?

This shorter expression is an abbreviation of, un de ces quatre matins (one of these four mornings), which is thought to have first appeared in the early 19th Century. 

The reason behind the use of number four is difficult to explain. The number appears in many French expressions and is thought to represent something that is relatively small or short - in this case, happening within the next few days, in the near future.

Examples of expressions including quatre:

• à quatre sous - It’s worth pennies

• Dire ses quatre vérités - Telling it like it is

• Couper les cheveux en quatre - Splitting hairs

• Ne pas aller par quatre chemins - Don’t beat around the bush

• Aux quatre coins du monde - To the four corners of the world

• Habillé à la 6, 4, 2 - Dressed badly

• Entre quatre yeux - Talk with sincerity or “We need to talk”

Another French expression featuring what might appear to be a random number is, dans 15 jours (in 15 days), which is actually used to say, in a fortnight.

How should you spell un de ces quatre?

If you find yourself writing this phrase, you might be tempted to add an ‘s’ at the end of quatre (to make an agreement with ces) - but this would be a mistake. 

In French, grammatical agreement (l’accord) refers to the correct termination of verbs, nouns, adjectives or other words, regarding things like gender (masculine or feminine) and numbers (plurals), according to their subject.

Numbers used to count a specific quantity, never take the ‘s’ agreement. For example, quatre matins (four mornings) - the number is singular and the noun is plural. They are described as invariable (invariable to mean that their spelling never changes).   

Even though matins has been dropped from this expression, they are still represented through use of ces (these). 

You might even come across the spelling, un de ces quat’, which mimics the everyday ‘lazy’ pronunciation of this expression (the final re becomes silent). 

Read more: René, Renée: navigating subtle gender differences in French forenames

Read more: France’s ‘inclusive writing’: have you spotted examples like ami.e.s?

When do you say un de ces quatre?

As a rule of thumb, you can slide this phrase into any context referring to the near future - for example, as a substitution for bientôt (soon). 

• À un de ces quatre. - See you soon.

• Appelle-moi un de ces quatre ! - Call me at some point soon!

• On va prendre un verre ensemble un de ces quatre ? - Shall we go for a drink together sometime?

• Un de ces quat’, on va partir loin d'ici. - One of these days, we are going to go far away from here. 

To whom do you say un de ces quatre?

This phrase is considered informal and should be reserved for family and friends. 

You will not see this phrase written down often, except in text messages or scripted dialogue. 

Read also: Exploring French farewells: the rise of 'belle journée' and its cultural impact